The present invention relates in general to wiring, cabling, wiring harnesses and cable ties. More particularly the present invention pertains to the assembly and routing of wires in a cable or wiring harness when a generally right-angled junction or similar wiring breakout is required to be made from the trunk in order to form a branch line.
Wiring harnesses are typically used for situations where the number of wires to be routed through a unit is significant and whereas a result of the number of wires, space considerations must be specifically addressed. In stationary units such as electrical equipment cabinets and consoles the multiple strands of insulated wire can usually be left uncovered and secured together by nylon wire ties. The conventional wire ties typically include a saw-tooth band and a receiving and interlocking head. These two components are typically molded as a one-piece unitary member. When the proper orientation is established and the band correctly inserted into the head, the saw-teeth of the band become interlocked with the locking tab on the interior of the head, thereby preventing the band from being loosened. The saw-tooth configuration allows the band to be tightened into a smaller encircling loop thus allowing the tie to be extended around a bundle of wires and tightened so as to hold that bundle of wires together. When the secured wiring harness is routed through the unit these wiring ties may be used with mounting blocks or anchor blocks which may either be fastened to the walls or floor of the console by threaded fasteners or adhesively attached so as to fix the wire tie to a specific location on the surface or side wall of the cabinet or console. By the use of such anchor blocks the wiring harness is fixed in position including the main trunk and all branch lines which are split out from the trunk.
With stationary cabinetry and units of the type described there is typically very little movement, virtually no vibration and no exposure to contaminant fluids or chemicals. In these situations there is little if any concern that the insulation on the individual wires will become abraided or cut. Even if a small break or cut occurs, without the presence of fluids or chemicals, electrical shorts to the chassis are unlikely.
When a wiring harness is created for a motor vehicle there are concerns that the movement of the vehicle, shock impacts and vibrations could lead to cuts and abrasions to the insulation of the wires, especially in those areas where the wiring harness must be routed up and over or around an edge or sharp corner. There is also a concern that various liquids and chemicals may splash up or leak onto the wiring harness and thus any breaks in the insulation of the individual wires could result in electrical shorts. While some electrical shorts may not be significant, others could be significant, resulting in motor vehicle failure or an inoperative condition to some critical portion of the vehicle.
In order to minimize these concerns a conduit or sheath is typically used in motor vehicle wiring as an enclosing sleeve over the trunk and branches of the wiring harness. Although this enclosing sleeve is frequently slit lengthwise in order to allow breakout exiting of some of the wires from the main trunk in order to create a branch line, this enclosing sleeve does protect the harness wires from cuts or abrasions to the wire insulation.
When wires are pulled from the trunk for a breakout branch, there is still a desire to run these branch wires through a protective enclosing sleeve. It is also important for the branch sleeve to be secured in position up against the trunk sleeve. There are presently three basic ways to address these needs. One way is to securely tape the branch sleeve directly to the trunk sleeve. Another way is to use a rigid, clam-shell, T-junction clamp. A third way, but one which is really not suitable due to the possible damage to the wires, is to use several wire ties for the trunk sleeve on either side of the breakout branch as well as for the branch sleeve.
The drawbacks with the taping method include the time which it takes and the non-uniformity of the junction. Since taping techniques vary widely with different assembly workers the wiring harness junction will vary from harness to harness, even with the same worker. There simply is no standard as to the taping practice nor any established or predictable quality level. The drawbacks with the snap-fit, clam-shell structure include its size and rigidity and its fixed design. The rigidity of the structure forces either an oversizing so that one size will fit a majority of the trunk-branch junctions or alternatively a large number of different units must be manufactured so that they can be more closely sized and tailored to the specific junction. The greater the number of different sizes, the greater the molding costs and the greater the inventory inefficiencies. If there would be ten or twelve standard sizes for this clam-shell junction clamp, then these would have to be inventoried and provided with a wiring harness size range so that the assembly worker would know specifically which style to use at which point in the wiring harness.
With the wiring harness junction clamps there is a desire for some flexibility as it may be, if not necessary at least preferred, to move or flex the branch line slightly relative to the trunk so as to establish a preferred fit or routing through certain clearance areas and around specific components. The rigid clam-shell design does not permit such flexibility and movement in the orientation of the split-out branch.
In the art of T-junctions and connections for trunk lines and breakout branch lines there are several patent references. Many of these references pertain to pipe joints and a representative sampling of such patent references is listed below:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 5,020,832 Coblentz June 4, 1991 4,168,091 Boomgarden et al. September 18, 1979 4,691,945 Cottrell et al. September 8, 1987 3,944,260 Petroczky March 16, 1976 4,227,667 Dickerson October 14, 1980 ______________________________________
In order to address all of the concerns which have been mentioned, the present invention has been created. The present invention provides as a one-piece, unitary unit a flexible covering panel for the trunk and for the branch at their junction location. This flexible covering panel is molded in combination with wiring ties in order to secure one portion of the covering panel to the trunk and to secure another portion of the covering panel to the branch. Several variations are possible and contemplated within the scope and teachings of the present invention.